Valve control arrangement for reversible motors,especially for compressed-air rotary-piston motors



Feb. 11. 1969 H. J. FEHLINGS 3,426,648

VALVE CONTROL ARRANGEMENT FOR REVERSIBLE MOTORS, ESPECIALLY FOR COMPRESSED-AIR ROTARYPISTON MOTORS Filed Sept. 25, 1965 Sheet of 5 AWL-wrap HER BER T a. FfHLl/VGS B Y A TTOR NEY EH LINGS 3,426,648 R R L RSIBLE MOTORS ESPECIALLY RO Y-PIS TON MOTORS Sheet 3 of 5 Feb. 1 1, 1969 VALVE CONTROL FOR Filed Sept. 23, 1965 x i I I Awe-wrap HERBER J; FH/L/ms ATTORNEY J. FEHLINGS 3,426,648

ECIALLY Feb. 11. 1969 H.

VALVE CONTROL ARRANGEMENT FOR REVERSIBLE MOTORS, ESP

FOR COMPRESSED-AIR ROTARY-PISTON MOTORS Sheet 3 of 5 Filed Sept. 25, 1965 k as a! O HERBERT J. Ff/fL/NGS United States Patent P 35,151 US. or. 91-421 5 Claims Int. Cl. F01c 3/02; F1510 11/10, 13/042 ABSTRACT OF THE DISCLOSURE A reversible pneumatic rotary motor including a pair of ports one to each side of the motor, either port serving as an outlet for exhaust air from the motor upon selection of the other as an air inlet, having a live air feed control arrangement comprising a live air handle having an inlet control valve selectively operable to allow flow of operating air to a selected one of the ports, and a nonreturn spring loaded valve interposed between the inlet control valve and the motor operable in response to live air flowing in a selected passage to one port of the motor to allow exhaust of air from the other port of the motor.

For the control of reversible compressed-air rotarypiston motors, reversing elements in the form of fourway manual control slide valves or four-way valves are known, which are built into or on to the machine and are actuated by hand, together with the inlet valve or separately as preselector control, for running of the motor to right or left, before operation of the inlet valve. The disadvantage of these control arrangements consists in that in each case the reversing slide valve and the inlet valve must be operated separately, or on the other hand if operation is effected simultaneously the force strain to be mastered by the hand is undesiredly great.

Moreover in the case of the reversing slide valves the sliding surfaces, in order to close off completely tightly, must be fitted in with minimum possible clearance, so that the generally known difficulties occur on wear and replacement.

For the control of remotely operated compressed-air motors, air-supply controls in the form of four-way manual control slide valves or the like are known, which in practice have proved disadvantageous in so far as the air issuing from the motor by way of one of the two connection hoses at the manual control slide valve annoys the operator by noise and soiling with water or oil. Moreover the alternate flow of compressed air and exhaust air through the hoses is disadvantageous in so far as on the one hand the hose crosssection must be generously dimensioned for the exhaust side in each case, so that no reduction of performance of the motor occurs, and on the other hand the oil for the motor lubrication, accompanying in air admission through a hose, is blown out again on switching over.

Moreover lifting gear motors having only one compressed air supply conduit and two air-discharge conduits for two control pistons with air-discharge control arrangements are known, the disadvantage of which consists in that a crack in the air-discharge conduit causes sudden starting up of the motor and consequently can lead to accidents.

/With the already known compressed-air control arrangements for compressed-air motors with built-in, pressure-medium-operated, spring-loaded friction brake (winch motors) one is only able to raise slowly through 3,426,648 Patented Feb. 11, 1969 the partly released rubbing brake. Slow lowering of a load is also possible only through the rubbing brake. Due to this on the one hand great wear occurs in the brake parts, and also a raised load will drop with maximum speed on failure of the brake. Only a quick-reaction switch-over to lift could prevent this dropping.

The invention relates to a valve-control arrangement for reversible motors, especially compressed-air rotarypiston motors, for the alternate opening of the air inlet to the one side of the motor and the air outlet from the other side of the motor with simultaneous blocking of the other air inlet and outlet, in which the abovedescribed drawbacks are avoided. The invention avoids the hitherto usual four-way slide valves due to the fact that in the compressed-air supply conduit there is inserted a two-way valve, which directs the compressed air to the one or the other side of the motor, and in the two air-supply paths between inlet valve and motor there is arranged in each case a non-return valve controlling the air outlet, the valve space of which is connected with the air inlet conduit in such manner that it is moved into the closed position by the air flowing to the motor, while the other non-return valve is held open.

This control arrangement on the one hand offers the advantage of simplicity of the two-way valve used, and also the possibility of placing the non-return valve in the vicinity of the motor, so that the air-supply conduit which is not in action is not loaded by the exhaust air and the operator cannot be annoyed by soiling.

As two-way valve there is preferably used an inlet valve which comprises a ball valve in each of two passage bores and a rotatable shifting body which on rotation out of its catch position lifts the one or the other valve ball away from its seating. The ball not influenced by this shifting body is then pressed upon its seating by the arriving compressed air and thus blocks oil the second air-supply path to the motor.

The shifting body of this double-ball inlet valve can be constructed in various manners. In one expedient form of embodiment the shifting body, formed in a manner known per so as a rotary handle of sleeve form, cornprises a radial pin which extends through a transverse slot in the valve housing between the two valve balls. By operation of the rotary handle in the one or the other direction then the one or the other valve ball is lifted. The rotary handle, arranged coaxially with the valve body, is spring-loaded and the pin secured on it extends through an arcuate slot in the valve housing, the ends of which slot limit the rotational movement of the sleeve. A detent can be provided in the slot for the middle position.

In another form of embodiment according to the invention as shifting body there serves a rotatable shifting bolt, which is formed with flattened portions in the region of the valve balls, against which in each case there bears a valve ball, which is lifted away from the valve seating on rotation of the shifting body. The rotational movement is limited by the encounter of the other flattened portion with the other valve ball situated on the valve seating.

The non-return valves to be used according to the invention can be formed in various manners, but the invention provides two particular forms of embodiment. In one case the two non-return valves consist of balls in coaxial, mutually opposed valve chambers, which are both connected to the exhaust opening of the motor; here the two balls are connected with one another .in force-locking fashion. This simply produced double non-return valve is situated in a connecting conduit between the two air inlet conduits, namely expediently in the vicinity of the motor, and the outlet for the exhaust air is arranged in this connection conduit between the mutually opposite valve seatings.

On operation of the inlet valve the one non-return valve ball is pressed by the entering air current on to its valve seating so that the outlet from this side is closed. The opposite valve ball is pressed away from the valve seating by a connection piece, preferably a compression spring, guided in the outlet bore between the two valve seatings, so that the air issuing from the motor can escape past the pressed-away valve ball and the thrust piece. As further solution of this problem, two non-return valves are proposed which are arranged similarly and oppositely between the two inlet conduits. Each of these non-return valves is preferably constructed as a spring-loaded control piston so that on the spring-loaded side it possesses a valve plate or cone which closes the outlet and on the pposite control side it possesses a diaphragm or a piston face, defined with soft packings, of larger area than the valve plate.

On air admission by operation of the double inlet valve the piston face or diaphragm facing the inlet conduit is so charged with air that the valve plate sealing off in the other air conduit is lifted away from the valve seat, so that the air flowing out of the motor can escape.

By reason of the regulable outlet throttling which can be achieved therewith, the last-mentioned form of embodiment is especially suitable for compressed'air rotary-piston motors with built-in, pressure-medium-operated, spring-loaded, friction brake, such as are mostly used in compressed-air lifting gear. The outlet throttling according to the invention ensures that slow starting-up of the motor is possible only after complete release of the brake, even in the lowering of a load, and a load once lifted is automatically held even on failure of the springloaded brake.

Further advantages of these control arrangements according to the invention are to be seen in the functional arrangement of the supply hoses leading to the motor, through which flow takes place in only one direction and which act at the same time as control conduit, while the exhaust air can escape directly from the motor.

A number of especially expedient forms of embodiment of the invention are explained in the drawing.

FIGURES 1 and 2 explain the control of a rotary-piston motor, utilising two different non-return valves.

FIGURE 3 shows inlet and non-return valves in one form of embodiment, the motor being omitted.

FIGURE 4 is -a section along the line IVIV in FIG- URE 3.

FIGURE 5 is a section along the line VV in FIG- URE 3.

FIGURE 6 shows another form of embodiment of the invention in section, the motor being omitted.

FIGURE 7 is a section along the line VIIVII in FIG- URE 6.

FIGURE 8 is a section along the line VIIIVIII in FIGURE 6.

FIGURES 1 and 2 explain the application of the invention to an ordinary compressed-air rotary-piston motor 1 having two symmetric inlet and outlet pasages 2, 3 for the compressed-air. These passages are connected with the inlet valve by means of ordinary conduits, such as compressed-air hoses 4 and 5. The two-way valve in all cases possesses a valve housing 6, in which there are inserted two valve balls 7, preferably of synthetic plastics material, which are pressed by the pressure medium flowing in through the passage 8 in the lubricator 9 on to the valve seatings formed in the two passage bores 10.

In the form of embodiment according to FIGURE 3 an arcuate slot is machined in laterally beside the valve balls in the valve housing, which slot has in the middle a small bulge 12 towards one side. On the valve housing 6 and the lubricator 9 known per se a sleeve 13 is rotatably mounted and axially spring-loaded by means of a spring ring 14. Into annular grooves of the valve housing 6 there are inserted O-rings 15, which seal off the gap between valve housing and rotatable sleeve. The rotatable sleeve 13 is provided with a small protruding part 16, into which according to FIGURE 4 a peg screw 17 is screwed so that its peg 18 extends through the slot 11 between the two valve balls 7. When the valve is in the closed position the peg 18 is pressed by the spring-loaded sleeve 13 into the bulge 12, so that the sleeve 13 can snap in.

On rotation of the sleeve 13 the peg presses one of the two balls 7 radially away from the valve seating, so that the one valve is opened and the pressure medium can flow through one of the bores 10. The same peg 18 in each case limits the range of rotation of the sleeve 13 by abutting at the end of the slot 11. On turning of the sleeve back into the closure position as illustrated in FIGURE 4 the valve ball 7 is pressed on to its valve seating again by the flow of the pressure medium, and thus the air passage is shut off.

The double ball non-return valve according to FIG- URES 3 and 5 can be connected directly or indirectly, for example by means of flexible conduits, with the various illustrated inlet valves. Its valve body 19 possesses two passage bores 20, which can be connected with the two bores 10 of the inlet valve on the one side and the inlet openings 2, 3 of the motor on the other side. The two bores 20 are further connected through the two valve chambers 21 and the transverse passage 22 with the outlet passage 23.

A compression spring 24 guided in the transverse passage 22 is so dimensioned in length that it presses the valve balls 25 arranged in the valve chambers 21 away from the valve seatings 26. The valve chambers 21 are expediently closed by threaded plugs 27. These plugs have three or four pins 28 for the guidance of the ball-s 25, and seal off the valve chamber 21 through the O-rings 29 inserted into the annular grooves.

The manner of operation of this device consists in that on actuation of the inlet valve pressure medium flows through one of the two passage bores 20, and through the inlet channel 2 to the motor, and finds a resistance for the drive of the motor; at the same time a part of the pressure medium flows into the valve chamber 21 and the outlet passage 23, the corresponding valve ball 25 being pressed immediately on to its seating 26, so that now the pressure builds up for the drive of the motor.

The ball 25 arranged in the other valve chamber 21 is pressed away from the valve seating by the compression spring 24 guided in the transverse passage 22, so that the pressure medium issuing from the motor can escape through the second valve chamber 26, past the second valve ball 25 and the compression spring 24, through the outlet passage 23.

The inlet valve as illustrated in FIGURES l, 2, 6 and 8 possesses a valve housing 6 in which two valve balls 7, preferably of synthetic plastics material, are pressed by the inflowing pressure medium on to the valve seatings formed by the two passage bores 10.

In the valve housing 6, perpendicularly of the axis of the valve, there is mounted a shifting bolt 30 with a valve head 32 fastened by the clamping pin 31, which head serves for the operation of the valve. This bolt 30 has a flattened portion 33 on both sides in the region of the two valve balls 7, against each of which flattened portions a valve ball 7 places itself eccentrically of the central axis of the bolt. The valve chamber is sealed off against air losses by the O-rings 34 inserted into the annular grooves. The valve housing 6 is here again closed 3y the lubricator 9 known per se, which serves as han- On rotation of the bolt 30 one of the two balls 7 is pressed radially away from the valve seating, so that the valve is opened and the pressure medium can flow through one of the two bores 10. The rotational movement is limited by the striking of the flattened portions 33 on the still sealing valve ball 7. On turning back of the bolt 30 into the closure position as illustrated in FIG- URE 6 the pressed-away ball 7 is pressed on to its valve seating again by the pressure medium, the application pressure of the two valve balls 7 giving a detent position to the bolt 30.

The double non-return valve according to FIGURES 6 to 8 can be connected directly or indirectly for example by means of flexible conduits with every double inlet valve (FIGURES 3 and 4 or FIGURES 6 and 8). The valve body 35 is so pierced by two passage bores 36 that these, together with the two passage bores of the double inlet valve on the one side and the two inlet openings 2, 3 of the motor on the other side, form a continuous passage in each case. From each of the two bores 36 a branch passage 37 leads into the valve chamber 38 of the spring-loaded side of the one control piston 39 and a branch passage 40 leads into the valve chamber 41 of the control side of the other control piston 42.

The two valve pistons 39 with O-rings 43 laid into annular grooves are pressed by the compression springs 44 upon the valve seatings formed by the outlet bores 45. The outlet bores 45 open into the outlet passage 46.

The control pistons 42 with the O-rings 47 are let, with their rods 48, into the valve pistons 39, as shown in FIG- URE 6., so that control piston 42 and valve piston 39 are one unit.

The manner of operation of these double non-return valves consists in that on actuation of the inlet valve pressure medium flows through one of the two passage bores 36 and to the inlet passage 2 of the motor and in the drive thereof finds a resistance, but at the same time exerts a pressure upon the piston face of the control piston 42. The control piston charged with the pressure medium, as a result of its larger cross-section, presses the valve piston 39 away from its seating, so that the pressure medium issuing from the motor can escape through the valve chamber 38, past the pressed-away valve piston 39, through the outlet bore 45 and the outlet passage 46.

I claim:

1. A live air feed and exhaust valve control arrangement for a reversible pneumatic rotary motor having a pair of ports each in communication with a separate side of the motor one of the ports serving as an outlet for exhaust air from the motor upon selection of the other as an inlet of live air to the motor, comprising a pair of conduits each conduit being adapted for connection with a separate port of the motor, a live air inlet control unit including an inlet air supply chamber with which each conduit has a separate connection, manipulative valve control means in the control unit for selectively communicating one of the conduits with the chamber and blocking ofl. the other, and exhaust valve control means interconnected in the conduits having automatic response to inlet live air flowing in a selected one of the conduits to communicate the other conduit to exhaust, wherein the manipulative valve control means includes a pair of valve elements in the supply chamber which are normally closed by inlet pressure, each normally blocking live inlet air flow from the supply chamber to a separate one of the conduits, lever means manually actuable to unseat a selected one of the valve elements from the related conduit, and resilient holding means for releasably maintaining the lever in its actuated condition.

2. A live air feed and exhaust valve control arrangement for a reversible pneumatic rotary motor according to claim 1, wherein the exhaust valve control means includes an exhaust chamber having a separate branch connection with each conduit, and spring loaded valve means in the exhaust chamber normally establishing communication of the exhaust chamber through both branches with the conduits, the spring loaded valve means being responsive to live inlet air passing through a selected one of the conduits to simultaneously block communication of the selected conduit with the exhaust chamber and to maintain communication of the other conduit with the exhaust chamber.

3. A live air feed and exhaust valve control arrangement for a reversible pneumatic rotary motor according to claim 1, wherein the exhaust valve control means includes exhaust passage means, a pair of spring loaded valve elements each normally biased to block communi cation of its related conduit with the exhaust passage means, and each valve element being responsive to flow of live inlet air in the related conduit to communicate the exhaust passage means with the other conduit.

4. A live air feed and exhaust valve control arrangement for a reversible pneumatic rotary motor according to claim 1, wherein the exhaust valve control means is located in close proximity to the motor, and the connection of the supply chamber with the pair of conduits is located remotely relative to the exhaust valve control means.

5. A live air feed and exhaust valve control arrangement for a reversible pneumatic rotary motor according to claim '4, wherein lubricating means is provided in the control unit for lubricating inlet air flowing to the supply chamber.

References Cited UNITED STATES PATENTS 2,257,893 10/1941 Van Sittert 91-121 2,680,016 6/1954 McLeod 91-420 3,299,781 1/1967 Law 91-58 3,274,902 9/ 1966 Kleckner 91-420 2,293,555 8/1942 Mercier 91--448 2,343,912 3/ 1944 Lauck 91-447 2,494,633 1/ 1950 Schlicksupp 137-609 2,575,940 11/1951 Brown 137-609 2,648,346 8/ 1953 Deardortf 91-447 2,691,964 10/ 1954 Stickney 91-420 2,750,960 6/1956 Hansen et al 137-609 2,800,110 7/1957 Haarmeyer 91-447 2,984,985 5/ 1961 MacMillin 60-97 3,002,498 10/1961 Quayle 91-447 3,273,467 9/1966 Allen 91-420- FOREIGN PATENTS 84,323 1/1957 Netherlancl.

PAUL E. MASLOUSKY, Primary Examiner.

US. Cl. X.R. 91-420, 468; 137-5962, 609 

